1. Field of the Invention
In general, the present invention relates to electrodes that are placed on the skin of a patient. More particularly, the present invention relates to the physical structure of such electrodes and the methods used to attach such electrodes to the skin.
2. Description of the Prior Art
There are many types of medical equipment that gather and process electrical signals generated from within a patient's body. For instance, an electrocardiogram instrument detects electrical nerve impulses generated by the heart. Those detected impulses are then converted into a graphical representation so that the heart's nerve impulses can be viewed and analyzed by a doctor. Many other pieces of medical equipment exist that detect electrical impulses from other organs of the body, such as the brain, lungs and uterus.
In order for a piece of medical equipment to detect an electrical impulse from within the human body, some type of electrical lead must be attached between the medical equipment and the body. The electrical lead must also mechanically attach to the body so that an electrical impulse generated within the body can be transmitted into the electrical lead and back to the medical equipment.
There are many types of electrical lead terminations that engage a patient's body and receive electrical impulses. Some of these prior art terminations are intrusive, in that they have an electrode lead that penetrates the skin or is introduced within an orifice of the body. However, for many types of medical testing, such as electrocardiograms, passive termination electrodes are used. A passive termination electrode is typically formed as a conductive pad. The conductive pad is glued, strapped or taped to the skin. The passive termination electrode detects electrical impulses through the skin without having to penetrate the skin. Such prior art passive termination electrodes are exemplified by U.S. Pat. No. 5,511,548 to Riazzi, entitled Biomedical Electrode Having A Secured One-Piece Conductive Terminal.
Passive termination electrodes that attach to the skin come in a wide assortment of sizes and configurations depending upon the intended application of the termination electrode. In many cases, the termination electrode is shaped to be round. This is done for two purposes. First, with a round termination electrode, the orientation of the termination electrode is irrelevant when it is placed on the skin. Second, a round termination electrode does not have salient points or corners that can chaff against clothing or folds in the skin, therein causing the termination electrode to peel away from the skin.
In many medical testing or monitoring procedures, multiple termination electrodes are attached to a patient's body. For instance, during an electrocardiogram, it is not uncommon for several termination electrodes to be attached to a patient's chest. The position of where the termination electrodes attach to the body are very specific. In order to obtain accurate data, each termination electrode must be attached to the body within a small, specific area of the body. However, when traditional round termination electrodes are used, the round shape of the termination electrodes prevents the termination electrodes from being attached to the body in close proximity without overlapping. Often a physician is required to custom cut termination electrodes so that the physician can place all the termination electrodes on the area of the body without overlapping. This is especially true with smaller patients, such as children, that have small body frames.
Furthermore, many medical testing and monitoring procedures, such as cardiac stress tests, require that a patient wear multiple termination electrodes as the patient exercises. Accordingly, there is a great deal of body movement during the test. When prior art electrode terminations are cut or are overlapped, there exist gaps and points that can cause discomfort to the patient as they move. Furthermore, the gaps and points tend to peel away from the skin as the patient moves, especially if the termination electrode is being contacted by clothing or a moving arm.
A need therefore exists for an improved passive termination electrode that enables multiple termination electrodes to be placed in a dense concentration on a small patch of skin without the termination electrodes overlapping or requiring cutting. A need also exists for a termination electrode that can be placed on the skin in dense concentrations without producing gaps or salient points that can cause the termination electrodes to prematurely detach. These needs are met by the present invention device as it is described and claimed below.